The field of the invention is in the radar art and more particularly in the art of fire-control radars having active missile guidance.
Modern state-of-the-art fire-control radars with active missile guidance cw beams use a stationary filter in front of a receiver-protector to prevent the transmitter leakage from saturating the receiver and from keeping the receiver protector "on" continuously. The stationary filter parameters place certain bounds on the missile guidance frequency that precludes the use of frequency agility.
The following patents are of general interest in the background of the invention and the best know prior art. U.S. Pat. Nos. 3,027,525 issued to patentee E. Salzberg; 3,289,112 issued to patentee C. E. Brown; 3,426,299 issued to patentee S. Dixon, Jr.; 3,648,197 issued to patentee W. Siekanowicz; and 4,023,169 issued to patentee E. Kolp et al. Pending patent application Ser. No. 854,449 dated Nov. 23, 1977 by H. Goldie et al entitled "Microwave YIG Power Limiter Using Electrically Thin Iris," also discloses a passive ferrite power limiter that is suitable for use in the combination comprising the present invention.